Rotary engine.



DE WITT W. GARRABRANT & J. L. BURDGE.

ROTARY ENGINE. APPLICATION FILED JAN. 20, 1909.

Patentefi Sept. 28, 1909. 2 SHEETS-SHBET 1.

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g j DE WITT W. GARRABRANT 6: J. L. BURDGE. i ROTARY ENGINE.

APPLIGATION FILED JAN. 30, 1909 935,489, Patented Sept. 28, 1909.

2 SHEETS-SHEET 2.

v (7 adepfizTBary c UNITED STATES PATENT ()FFTCE.

DE WITT W. GARRABRANT AND JOSEPH L. BURDGE, OF TRENTON, NEW JERSEY.

ROTARY ENGINE.

To all whom it may concern:

Be it known that we, DE IVITT IV. GARRA- BRANT and J OSEPH L. BURDGE, citizens of the United States, residing at Trenton, in the county of Mercer and State of New J ersey,

The primary object of the present invention is to provide an engine of this general type having abutment means of novel con structlon, one feature of novelty residingin the relation of parts whereby the abut-- ment serves as a slide valve and directly controls the admission of fluid to the cylinder and another feature of novelty residing in the provision of means for automatically operating the abutment instead of relying on the piston as an abutment operating.

means, as in former devices. By virtue of this arrangement strain and wear on the internal parts of the engine are materially reduced and the life of the engine is prolonged and its more efficient operation insured.

The invention includes as a further novel feature the provision of spring means for holding the abutment in close contact with the working face of the piston body in order to prevent the back flow of steam from the admission to the exhaust side of the cylinder or vice versa.

The foregoing objects are carried out in a structure which is characterized by simplicity of details and arrangement, compactness, inexpensiveness and strength.

In the following description we have eX- plained in detail the construction of a preferred and advantageous form of the invention and such description is to be considered in connection with the acompanying draw ings.

The novel features of the invention will be set forth in language of the proper determinative scope in the claims appended to the description.

In the said drawings: Figure 1 is a central vertical section of an engine constructed Specification of Zetters Patent.

Application filed January 30, 1909.

Patented Sept. 28, 1909.

Serial No. 475,130.

in accordance with the present invention, the abutment being shown as in position to open the admission passages. Fig. 2 is a similar view, the abutment being in position to close the admission passages and the piston being removed in order to show more clearly the relation of certain packing rings which are associated with the piston. Fig. 3 is a vertical transverse section of the present engine. Fig. 4c is a detailed side elevation showing the fly wheel as constructed with a cam groove in its inner face. Fig. 5 is a detailed side elevation with the fly wheel partly broken away to show more clearly the relation of the operating elements on the abutment. Fig. 6 is a detailed perspective view of a connecting element between the abutment and the fly wheel for operating the former from the latter. Fig. 7 is a detailed perspective view of the abutment and Fig. 8 is a detailed perspective view of the piston body.

Similar characters of reference refer to corresponding parts throughout the several views.

The engine casing is, as usual, made in half sections, as l, which have projecting flanges, as 2, the latter being connected by bolt and nut fastenings 3. The flanges 2 have projecting from their lower portions integral shoes 4 which form a supporting base or pedestal for the engine. The sec tions 1 are each constructed with annular grooves 5 which register and form a piston chamber, as 6, the chamber 6 being preferably of annular cross section. The sections 1 include also opposed central or hub portions 7 as shown in Fig. 3, through which the shaft 8 extends. The shaft 8 carries the belt wheel 9, the fly wheel 10 and the piston body 11. The latter comprises a ring portion, as 12, which is keyed upon the shaft 8 and is disposed in the space between the hub portions 7 and also a piston head 13 which is of disk shape and is disposed in a plane at substantially right angle to the ring por tion 12, being connected therewith by a web 14. The ring portion 12 is preferably provided with an offset projection, as 1%, which is located adjacent the bearing surface of the head 13 and which serves a purpose to be later explained. The head 13 is preferably provided with suitable packing rings, as 15, to cooperate with the surface of the chamber 6 to prevent the escape of the motive fluid in either direction. The hub portions '7 are provided with annular grooves 16 in which are disposed annular packing rings 17 which bear upon each side of the ring portion 12 and are held in contacting engagement therewith by spiral springs 18 arranged in recesses which open into the grooves 16. In order to effectually compensate for wear the tension of the springs 13 may be adjusted, set screws, as 19, being provided for this purpose. The sections 1 are likewise formed with radially disposed channels, as 20, which open into the chamber 6 and which register when said sections are assembled and afford a pocket for a radially slidable abutment 21. The latter is preferably of rectangular outline and has an axially extended stem 22 which projects beyond the engine casing and through a stufiing box, as 23, formed in the upper portion thereof. The abutment 21 is provided near its upper end with an opening 24 which is designed to establish communication between inlet passages 25 and 26. the former extending from said pocket to the chamber 6. It is obvious that when the opening 24 is out of register with the passages 25 and 26, the abutment 21 will shut off the communication between said passages and consequently the supply of steam to the chamber 6. The fly wheel 10 has its inner face provided wit-h a cam groove, as 10 by means of which the operative movements of the abutment are controlled. Accordingly, a connecting member, as 10 is employed, the C()11S1'1'11Ct1011 and arrangement of which will be clearly apparent by reference to Figs. 3 and 6. The member 1O comprises a straight stem which is movable axially in a suitable guide- 213*, as 27, and is held against displacement by a strap 23 which bridges said guide-way, the said stem terminatingat its upper end in an angular extension 29 and being provided at its lower end with a roller, as 30, which works in the groove 10 aforesaid. The extension 29 is formed with an aperture 31 which loosely surrounds the stem 22 of the abutment, the extension 29 being disposed between upper nuts 32 and a lower nut 33, the nuts 32 and 33 being threaded upon the stem 22. A cushioning spring 34 is interposed between the extension 29 and the nut 33 and serves to hold the abut-ment- 21 in close contact with the piston body 11, the latter having the face of the web 1-1 curved at an angle to and in continuation of the surface of the ring portion 12 and in conformity to the outline of the corresponding working portion of the cam groove 10*.

The inlet of fluid to the chamber 6 is controlled by the abutment 21 in the manner previously explained and the exhaust 0f the fluid is controlled by the piston 15 which traverses the exhaust passage 35 leading from the chamber 6 at a point comparatively near the admission passage 26. The arrangement of the passages 26 and 35 in propinquity is, of course, in order that the steam or other motive fluid may exert its full pressure on the piston for the greatest possible portion of a revolution thereof.

The operation will be obvious from the foregoing description. hen the abutment rests on the surface of the ring portion 12, as shown in Fig. -1, the opening 2 1 will establish communication between the passages and 26 and steam will be admitted to the chamber 6, thus driving the piston body in the direction of the arrow, the force of the steam being exerted on said body for themajor portion of a revolution thereof, until the piston 15 passes the exhaust passage 35, at which time the steam will exhaust from the chamber 6. As the piston body 11 draws ear the passage 35 the member 10 will raise the abutment 21, the extension 29 on said member during the upward movement thereof engaging the nuts 32 which are provided on the stem of the abutment and the abutment as it gradually moves upwardly, cuts off the supply of steam from the chamher 6 in the manner set forth during the period that the charge is exhausting through the passage 35. As soon as the piston 15 traverses the pocket 20, the abutment 21 is moved downwardly by the member 10 the latter of course following the outline of the groove 10 The abutment in its downward movement engages the projection 12*, the latter serving to hold said abutment in position to interrupt the communication of the passages 26 until the head 13 shall have passed by the latter, at which time the projection 12 leaves the abutment and the latter, now following the periphery of the ring portion 1.2, establish-es communication between the passages 25 and 26. It will thus be apparent that the projection 12 prevents the too early admission of steam into the chamber 6. The spring 34 as above stated, serves to hold the abutment in close contact with the piston body and also to take up shocks and vibrations caused by the rapid movements of the member 10.

By providing automatic operating means for the abutment and disposing such means exteriorly of the casing, the strain upon the piston body and the abutment will be minimized and the wear of these parts within the interior of the casing will be reduced. This prolongs the life of the engine and prevents leakage. This latter purpose is assisted by the spring 3% which takes up vibrations in the manner stated.

The parts are well balanced, simple and inexpensive in their construction and compact in their arrangement. The engine may be readily set up and dismantled for renewing or repairing the parts, is strong, not liable to leakage with consequent waste of power, and is efficient in operation.

Having fully described our invention, we claim:

1. In a rotary engine, a casing having an annular piston chamber, a shaft extending transversely of the casing, a piston mounted upon said shaft and comprising a ring portion, a piston portion and a web connecting the piston portion with the web portion and having its face curved in continuation of the curvature of the ring portion, said casing being provided with inlet and exhaust passages and with a pocket interrupting the inlet passages, an abutment movable in said pocket and having an opening which, in one position of said abutment, establishes communication between the inlet passages, and spring means associated with the abutment for holding the latter in close contact with the face of said piston body.

2. In a rotary engine, a casing having an annular piston chamber, a shaft extending transversely of said casing, a piston body mounted upon said shaft, said casing being provided with inlet and exhaustpassages, an abutment movable radially of said chamber along the line between the points of communication therewith of said inlet and eX- haust passages, a cam wheel mounted upon said shaft exteriorly of the piston, a reciprocatory member operated by said cam wheel, said abutment being provided with a stem projecting beyond said casing, said member having an extension formed With an opening to surround said stem, nuts arranged on said stem above and below said in one position of said abutment, establishes communication between the admission passages, said abutment bearing at all times against the edge face of said piston, the latter having a projection which engages and holds the abutmentin position to interrupt said passages until the piston head passes by the inlet passage.

4. In a rotary engine, a casing having an inlet passage, an abutment controlling the admission of fluid to said casing through said inlet passage, and a piston in said casing comprising a piston head and a ring portion, the latter having a projection adj acent the bearing face of the piston head and upon which the abutment engages.

In testimony whereof we have hereunto set our hands in presence of two subscribing witnesses.

DE IVITT WV. GARRABRANT. JOSEPH L. BURDGE.

lVitnesses L. D. SNYDER, r A. STECKEL. 

